Imaging technologies are used in a variety systems and applications, for example, automobiles, hand-held communications, defense, security and medical diagnostics. Sensors and other such structures can be manufactured from semiconductor materials, often at low cost. Moreover, the dimensions of a semiconductor sensor can be scaled to increase density and improve device performance. An active pixel sensor (APS) is one such device that can be made with light sensitive semiconductor materials. Reducing the dimensions of the APS (i.e., scaling to a smaller size) may increase pixel dark current and degrade image quality. Present APS structures may therefore be less desirable for many imaging applications.